Visible Photocatalytic Degradation Of Rhodamine Research Articles

2D/2D g-C3N4/TiO2 with exposed (001) facets Z-Scheme composites accelerating separation of interfacial charge and visible photocatalytic degradation of Rhodamine B

Z-scheme heterojunction was successfully constructed with (001)-TiO2 and g-C3N4 via electrostatically self-assemble. Z-Scheme heterojunction nanocomposites improve separation efficiency of photogenerated e−-h+ pairs, which strengthen visible photocatalytic elimination for Rhodamine B. The g-C3N4 with narrower bandgap not only forms a stable phase interface with (001)-faceted TiO2 nanosheets, but also provides high productivity of photo-excited charge carries. Meanwhile, the layered graphite carbon in g-C3N4 owns an excellent ability to transfer electrons. The RhB degradation rate of the g-C3N4/(001)-faceted TiO2 hybrid reach up to 99.9% under the visible light for 2 h. This study provided an efficient g-C3N4/(001)-faceted TiO2 photocatalyst with Z-Scheme heterojunction structure has emerged as a promising approach to perfect the photocatalytic capacity of photocatalysts.

Facile Synthesis of g-C3N4/TiO2/Hectorite Z-Scheme Composite and Its Visible Photocatalytic Degradation of Rhodamine B.

A novel g-C3N4/TiO2/hectorite Z-scheme composites with oxygen vacancy (Vo) defects and Ti3+ were synthesized by so-gel method and high temperature solid phase reaction. This composite exhibited high visible photo-catalytic degradation of rhodamine B (RhB). The apparent rate constant of g-C3N4/TiO2/hectorite was 0.01705 min−1, which is approximately 5.38 and 4.88 times that of P25 and g-C3N4, respectively. The enhancement of photo-catalytic efficiency of the composites can be attributed to the great light harvesting ability, high specific surface area and effective separation of electrons(e−) and holes(h+). The F element from Hectorite causes the formation of Vo and Ti3+ in TiO2, making it responsive to visible light. The effective separation of e− and h+ mainly results from Z-scheme transfer of photo-produced electrons in g-C3N4/TiO2 interface. The composites can be easily recycled and the degradation rate of the RhB still reached 84% after five cycles, indicating its good reusability.

Room temperature processed copper phthalocyanine nanorods: A potential sonophotocatalyst for textile dye removal

Efficient ultrasound assisted visible photocatalytic degradation of Rhodamine B with the chemically synthesized copper phthalocyanine (CuPc) nanorods at room temperature is reported. In order to get structural, morphological, and optical information, different characterization techniques are employed here. The characterization results indicate the formation of highly crystalline pure CuPc nanorods. Comparative studies for dye degradation of sono, photo and sonophotocatalysis are performed in this report. As a typical result, 81 % removal of organic pollutant is achieved by sonophotocatalysis within 60 min, whereas by sonocatalysis and visible photocatalysis, only 56.8 % and 22.8 % degradation efficiency are achieved respectively under the same experimental conditions. Ultrasound irradiation combined with visible light in sonophotocatalysis may produces synergistic effect that plays an important role, resulting in superior dye degradation performance. The plausible reaction mechanism is thoroughly discussed in this study. The influences of initial dye concentration, catalyst dosage, scavenger and enhancer on decolorization efficiency are also investigated.